Eight dead, 108 missing after US mudslide

Emergency officials have dramatically raised the number of missing persons in the aftermath of Saturday's deadly mudslide in Washington state, saying that 108 people are unaccounted for.

The new count was given by Snohomish County Emergency Management Director John Pennington at a televised press briefing Monday morning.

It comes in addition to the eight people confirmed dead, and the 12 injured in the catastrophe.

"We have 108 individual names, or likeness," said Pennington, who added that he expected the number to come down rather than increase as some of the people on the list came forward.

The news conference coincided with the resumption of rescue efforts which saw hundreds of rescuers scour through the tide of mud which swept away dozens of houses on Saturday, in the town of Oso some 100km north east of Seattle.

Rescuers did report hearing calls from the wreckage on Saturday but could not reach them as the mud was still fluid and caused rescuers to sink.

There were no signs of survivors in the Sunday search and Snohomish County Fire District 21 Chief Travis Hots said "the situation is very grim".